1,7

Conjecture: the only solutions for x!+y!=n^2 are x=0,0,0,1,1,1,2,4,4,4 and y=4,5,7,4,5,7,2,0,1,5 respectively.

Table of n, a(n) for n=1..10.

Added as a companion to A082871.

Sequence in context: A131118 A140765 A097541 * A079560 A330601 A088680

Adjacent sequences: A151816 A151817 A151818 * A151820 A151821 A151822

nonn

Farideh Firoozbakht, Jul 07 2009

approved